US6640597B2 - Method for reducing variance in the coolant consumption of components of a turbo-machine - Google Patents
Method for reducing variance in the coolant consumption of components of a turbo-machine Download PDFInfo
- Publication number
- US6640597B2 US6640597B2 US10/003,231 US323101A US6640597B2 US 6640597 B2 US6640597 B2 US 6640597B2 US 323101 A US323101 A US 323101A US 6640597 B2 US6640597 B2 US 6640597B2
- Authority
- US
- United States
- Prior art keywords
- tool
- holes
- longitudinal axis
- hole
- rotationally
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/18—Hollow blades, i.e. blades with cooling or heating channels or cavities; Heating, heat-insulating or cooling means on blades
- F01D5/186—Film cooling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P9/00—Treating or finishing surfaces mechanically, with or without calibrating, primarily to resist wear or impact, e.g. smoothing or roughening turbine blades or bearings; Features of such surfaces not otherwise provided for, their treatment being unspecified
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P2700/00—Indexing scheme relating to the articles being treated, e.g. manufactured, repaired, assembled, connected or other operations covered in the subgroups
- B23P2700/06—Cooling passages of turbine components, e.g. unblocking or preventing blocking of cooling passages of turbine components
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2230/00—Manufacture
- F05D2230/10—Manufacture by removing material
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2230/00—Manufacture
- F05D2230/90—Coating; Surface treatment
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2250/00—Geometry
- F05D2250/20—Three-dimensional
- F05D2250/25—Three-dimensional helical
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/47—Burnishing
Definitions
- the present invention relates to a method for reducing the variance in the coolant consumption of components of a turbo-machine, in particular a gas turbine, having one or more through-holes or drilled holes for the passage of a coolant.
- the invention relates also to a tool for performing the method.
- Sufficient and reliable cooling of components of a turbo-machine is an essential aspect for operating the turbo-machine.
- Highly cooled components such as, for example, turbine blades or combustor walls, are provided for this purpose with numerous cooling air holes, through which cooling air fed into the interior of the components passes and is released to the outside into the hot working medium.
- the pressure to improve the efficiency of modern gas turbines results in the necessity of minimizing the cooling air consumption while maintaining sufficient cooling of the components to be cooled.
- a minimizing of the cooling air consumption is achieved, on the one hand, by an optimized distribution of the cooling air holes, and, on the other hand, by reducing the hole diameters while simultaneously increasing their number.
- the holes are provided in the walls of the components to be cooled using modern manufacturing methods, such as, for example, laser drilling, laser cutting, electrochemical drilling, or spark erosion.
- these types of processing methods result in roughness of the surface inside the hole.
- the degree of roughness does not depend on the diameter of the hole, i.e., it is not reduced if the hole diameter is decreased.
- the diameter of cooling air holes in stationary gas turbines was about 1 to 1.5 mm a few years ago, today's cooling air holes are provided in the components with diameters in the range of 0.6-0.8 mm or less. This means that the surface quality or roughness inside the hole increasingly determines the flow-through of the coolant. This influence becomes noticeable mainly in the case of deep holes, as required, for example, in the trailing edge of cooled turbine blades.
- the roughness distribution in the holes occurs more or less randomly as they are produced.
- individual, fine rough points that may have a strong influence on the pressure loss across the hole, and therefore on the cooling air consumption, cannot be controlled, or can only be controlled insufficiently, by means of the known manufacturing processes.
- This random distribution of the rough points results in a wide variance of the cooling air consumption of the finished components, for example film-cooled turbine blades.
- the fine rough points occurring during the manufacturing of the cooling air holes change due to wear during operation of the components, so that the cooling air consumption of the components may rise over time in an undesirable manner.
- the present invention provides a method that reduces variance in the consumption of coolant by components of a turbo-machine, without the risk of later obstruction of the holes for the coolant by waste products.
- the invention provides a method for reducing the variance in the coolant consumption of a turbo-machine, in particular a gas turbine, having one or more through-holes or drilled holes for the passage of a coolant.
- the method includes reducing the surface roughness present in the holes after manufacturing by a mechanical reshaping or cold working of rough points that cause the surface roughness.
- the holes are finished with a tool in such a way that the rough points are evened out by the reshaping. This eliminates especially fine rough points, so that a clearly reduced variance of the cooling air consumption, for example, from blade to blade of a gas turbine, can be achieved.
- the method is especially suitable for finishing cooling air holes in components of a gas turbine, for example the cooling air holes in the combustor walls or turbine blades of the gas turbine.
- the reshaping of the rough points is preferably accomplished by a cold working process such as at least one of beating, pressing and rolling. Other similar shaping techniques can also be used for working out the rough points.
- the inventors have recognized that the relatively small rough points occurring in the holes do not necessarily require a cutting technique in order to improve the surface quality.
- the leveling of the rough points with a simple mechanical reshaping, for example by a cold working process that includes at least one of beating, pressing and rolling, has significant advantages over cutting techniques.
- the mechanical reshaping methods of the present invention simplify the finishing, and, on the other hand, prevent the creation of chips or other waste particles that could contaminate the components on the inside.
- the present method advantageously enables finishing the finished component, for example, in its already installed state in the machine, for example, in the gas turbine.
- the holes can be produced with their final diameter during production, since, during finishing according to the invention, the rough points responsible for the variance in flow are only evened out, without enlarging the originally planned hole diameter.
- the shaping of the rough points inside the holes is performed with a tool that neither cuts nor chips material that can be introduced into the hole manually or by machine.
- the tool has a pin-like shape so that, after being inserted into the cooling air hole, it extends at least over the entire length of the cooling air hole. It is then set into motion inside the hole by means of a suitable drive so as to act in a reshaping manner on the rough points.
- the movement of the pin-shaped tool generated by the drive may be rotating, translationally oscillating, or undulating. In principle, all types of movements can be used that cause the inner surface of the hole to interact with the pin-shaped tool that reshapes the rough points. In this way, the tool can be set into high-frequency oscillations, for example by means of ultrasound, in order to level the fine rough points inside the hole.
- the shape of the tool also can be varied within a broad range. It is possible to use a pin-shaped tool that is cylindrical or conical or has a cross-section that is variable over its length. It is also possible to use a tool extending helically or in a wave shape along its longitudinal axis.
- the tool is provided with a drive that acts on the tool, in the case of a non-rotationally-symmetrical design, with a translationally oscillating movement in the direction of the longitudinal axis, and a rotating movement around the longitudinal axis.
- the drive is realized preferably so as to create a translationally oscillating movement in the direction of and transversely to the longitudinal axis.
- FIG. 1 shows an example of a cooling air hole of a component prior to finishing.
- FIG. 2 shows a first example for a tool for finishing according to the invention.
- FIG. 3 shows a second example for a tool for finishing according to the invention.
- FIG. 4 a shows a section of a cooling air hole prior to finishing.
- FIG. 4 b shows a section of a cooling air hole after finishing.
- FIG. 1 is a schematic illustration of an example of the surface quality inside a cooling air hole of a gas turbine component.
- the cooling air hole 1 was placed into the wall 2 of the component using a suitable drilling method.
- fused-on layers 3 with numerous rough points 4 occur at the inside edge of the cooling air hole.
- the distribution and height of these rough points 4 vary from hole to hole. Especially in the small-diameter cooling air holes required today, these rough points significantly influence the flow of the coolant, and therefore of the coolant consumption.
- the rough spots 4 in the hole 1 are leveled or evened out in a reshaping manner using the present techniques.
- This finishing which is only a reshaping—and not a cutting or chipping—prevents the creation of chips or other waste products that could result in an obstruction of the cooling air holes during later operation.
- the leveling of the rough points nevertheless results in a significant decrease in variance of the coolant flow from hole to hole or from component to component.
- FIG. 2 shows an example for a tool for performing the method at hand.
- the tool includes a pin-shaped tool body 5 that in this example is constructed along its longitudinal axis with a variable cross-section.
- the pin-shaped tool body 5 is coupled with a corresponding drive (not shown) that drives the pin so as to perform an oscillating translation movement along its longitudinal axis as well as transversely to its longitudinal axis (indicated by arrows).
- the variable cross-section of the pin-shaped tool body 5 is realized in this example by ball-like enlargements 6 occurring at regular intervals along the longitudinal axis of the tool body 5 .
- the oscillating movement of the tool body 5 (indicated by the arrows) in a cooling air hole 1 such as illustrated in FIG. 1, causes the rough points 4 to be reshaped by a beating movement or to be pressed smooth.
- the material of the pin-shaped tool body 5 should have at least the same hardness as the material to be leveled.
- the tool body may be metallic or ceramic, or may also include another material that, for example, also may be coated with a hard layer.
- the diameter of the tool body should be smaller than the diameter of the cooling air holes. Preferably, such a tool body should therefore have a diameter of 0.5 mm or less.
- FIG. 3 shows another example of the shape of a pin-shaped tool body 5 for use in the method according to the invention.
- the pin-shaped tool 5 is constructed in a wave shape or provided with an undulating profile.
- the drive (not shown) drives this pin 5 in the cooling air hole so as to perform a rotating movement around its longitudinal axis as well as a translational movement along its longitudinal axis, as illustrated by the arrows.
- Such a design again achieves the same leveling effect on the rough points 4 as can be achieved with the tool body of FIG. 2 .
- the wave-shaped geometry of the tool body 5 in FIG. 3 preferably is realized with a screw-shaped or helical geometry of this body, but may be present also only in a single plane.
- FIGS. 4 a and 4 b finally represent a schematic illustration of a section of a cooling air hole 1 such as the one in FIG. 1 prior to and after the finishing using the method at hand.
- FIG. 4 a illustrates the still very rough, inner surface of the cooling air hole 1 with numerous rough points 4 .
- the rough points 4 are leveled so that a clearly smoothed, inner surface of the cooling air hole 1 exists (FIG. 4 b ).
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
- Drilling And Boring (AREA)
Abstract
Description
Claims (8)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE10064266 | 2000-12-22 | ||
DE10064266.7 | 2000-12-22 | ||
DE10064266A DE10064266A1 (en) | 2000-12-22 | 2000-12-22 | Method for reducing the variance in the cooling medium consumption of components of a turbomachine |
Publications (2)
Publication Number | Publication Date |
---|---|
US20020124615A1 US20020124615A1 (en) | 2002-09-12 |
US6640597B2 true US6640597B2 (en) | 2003-11-04 |
Family
ID=7668439
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/003,231 Expired - Fee Related US6640597B2 (en) | 2000-12-22 | 2001-12-06 | Method for reducing variance in the coolant consumption of components of a turbo-machine |
Country Status (3)
Country | Link |
---|---|
US (1) | US6640597B2 (en) |
EP (1) | EP1217172B1 (en) |
DE (2) | DE10064266A1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005052207A2 (en) | 2003-11-25 | 2005-06-09 | Touchstone Research Laboratory, Ltd. | Filament winding for metal matrix composites |
US20060235291A1 (en) * | 2005-03-24 | 2006-10-19 | Sultan Haider | Method for supporting an examination by means of an imaging diagnostic device |
EP2131109A2 (en) * | 2008-06-06 | 2009-12-09 | United Technologies Corporation | Counter-vortex, paired film cooling hole design |
US20170274493A1 (en) * | 2014-06-27 | 2017-09-28 | Applied Materials, Inc. | Chamber components with polished internal apertures |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2161411A1 (en) * | 2008-09-05 | 2010-03-10 | Siemens Aktiengesellschaft | Turbine blade with customised natural frequency by means of an inlay |
TW201207568A (en) * | 2010-08-12 | 2012-02-16 | Foxsemicon Integrated Tech Inc | Heat dissipation structure of LED light source |
US10337341B2 (en) | 2016-08-01 | 2019-07-02 | United Technologies Corporation | Additively manufactured augmentor vane of a gas turbine engine with additively manufactured fuel line extending therethrough |
US10436447B2 (en) * | 2016-08-01 | 2019-10-08 | United Technologies Corporation | Augmentor vane assembly of a gas turbine engine with an additively manufactured augmentor vane |
Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3195220A (en) * | 1963-12-30 | 1965-07-20 | Karl H Roehrs | Surface finishing apparatus and process |
GB1126020A (en) | 1966-12-12 | 1968-09-05 | Gen Motors Corp | Fluid directing structures, applicable for example, to gas turbine engines |
US3696504A (en) | 1971-08-11 | 1972-10-10 | John A Cupler | Method of performing sequential non-mechanical and mechanical machining operations along a common centerline |
US4398407A (en) * | 1981-01-26 | 1983-08-16 | Amsted Industries Incorporated | Sizing of powder metal parts |
US4453392A (en) * | 1982-05-11 | 1984-06-12 | Fiziko-Tekhnichesky Institut Akademii Nauk Belorusskoi Ssr | Method of hardening shaped surfaces by plastic deformation |
US4771627A (en) * | 1986-10-29 | 1988-09-20 | Mcdonnell Douglas Corporation | Stress-coining apparatus and method |
US5233738A (en) * | 1991-05-31 | 1993-08-10 | Robert Bosch Gmbh | Tool for fine machining |
US5247766A (en) | 1992-01-31 | 1993-09-28 | Kildea Robert J | Process for improving cooling hole flow control |
US5339523A (en) * | 1991-05-24 | 1994-08-23 | Matsushita Electric Industrial Co., Ltd. | Method of machining sleeve bearing |
US5501892A (en) | 1992-03-25 | 1996-03-26 | Ngk Insulators, Ltd. | Ceramic parts having small hole(s) and method of manufacturing the same |
US5644394A (en) | 1994-10-19 | 1997-07-01 | United Technologies Corporation | System for repairing damaged gas turbine engine airfoils |
US5826453A (en) * | 1996-12-05 | 1998-10-27 | Lambda Research, Inc. | Burnishing method and apparatus for providing a layer of compressive residual stress in the surface of a workpiece |
-
2000
- 2000-12-22 DE DE10064266A patent/DE10064266A1/en not_active Withdrawn
-
2001
- 2001-12-04 DE DE50106099T patent/DE50106099D1/en not_active Expired - Lifetime
- 2001-12-04 EP EP01128802A patent/EP1217172B1/en not_active Expired - Lifetime
- 2001-12-06 US US10/003,231 patent/US6640597B2/en not_active Expired - Fee Related
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3195220A (en) * | 1963-12-30 | 1965-07-20 | Karl H Roehrs | Surface finishing apparatus and process |
GB1126020A (en) | 1966-12-12 | 1968-09-05 | Gen Motors Corp | Fluid directing structures, applicable for example, to gas turbine engines |
US3696504A (en) | 1971-08-11 | 1972-10-10 | John A Cupler | Method of performing sequential non-mechanical and mechanical machining operations along a common centerline |
US4398407A (en) * | 1981-01-26 | 1983-08-16 | Amsted Industries Incorporated | Sizing of powder metal parts |
US4453392A (en) * | 1982-05-11 | 1984-06-12 | Fiziko-Tekhnichesky Institut Akademii Nauk Belorusskoi Ssr | Method of hardening shaped surfaces by plastic deformation |
US4771627A (en) * | 1986-10-29 | 1988-09-20 | Mcdonnell Douglas Corporation | Stress-coining apparatus and method |
US5339523A (en) * | 1991-05-24 | 1994-08-23 | Matsushita Electric Industrial Co., Ltd. | Method of machining sleeve bearing |
US5233738A (en) * | 1991-05-31 | 1993-08-10 | Robert Bosch Gmbh | Tool for fine machining |
US5247766A (en) | 1992-01-31 | 1993-09-28 | Kildea Robert J | Process for improving cooling hole flow control |
US5501892A (en) | 1992-03-25 | 1996-03-26 | Ngk Insulators, Ltd. | Ceramic parts having small hole(s) and method of manufacturing the same |
US5644394A (en) | 1994-10-19 | 1997-07-01 | United Technologies Corporation | System for repairing damaged gas turbine engine airfoils |
US5826453A (en) * | 1996-12-05 | 1998-10-27 | Lambda Research, Inc. | Burnishing method and apparatus for providing a layer of compressive residual stress in the surface of a workpiece |
Non-Patent Citations (1)
Title |
---|
European Search Report dated Apr. 15, 2003, no translation. |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005052207A2 (en) | 2003-11-25 | 2005-06-09 | Touchstone Research Laboratory, Ltd. | Filament winding for metal matrix composites |
US20060235291A1 (en) * | 2005-03-24 | 2006-10-19 | Sultan Haider | Method for supporting an examination by means of an imaging diagnostic device |
US7508204B2 (en) * | 2005-03-24 | 2009-03-24 | Siemens Aktiengesellschaft | Method for supporting an MRI examination by means of positioning and checking MRI accessory implementation |
EP2131109A2 (en) * | 2008-06-06 | 2009-12-09 | United Technologies Corporation | Counter-vortex, paired film cooling hole design |
EP2131109A3 (en) * | 2008-06-06 | 2014-01-01 | United Technologies Corporation | Counter-vortex, paired film cooling hole design |
US20170274493A1 (en) * | 2014-06-27 | 2017-09-28 | Applied Materials, Inc. | Chamber components with polished internal apertures |
US10189141B2 (en) * | 2014-06-27 | 2019-01-29 | Applied Materials, Inc. | Chamber components with polished internal apertures |
US11370078B2 (en) | 2014-06-27 | 2022-06-28 | Applied Materials, Inc. | Chamber components with polished internal apertures |
US11724353B2 (en) | 2014-06-27 | 2023-08-15 | Applied Materials, Inc. | Chamber components with polished internal apertures |
Also Published As
Publication number | Publication date |
---|---|
DE10064266A1 (en) | 2002-07-04 |
EP1217172A3 (en) | 2003-06-18 |
DE50106099D1 (en) | 2005-06-09 |
US20020124615A1 (en) | 2002-09-12 |
EP1217172A2 (en) | 2002-06-26 |
EP1217172B1 (en) | 2005-05-04 |
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Owner name: ALSTOM (SWITZERLAND) LTD, SWITZERLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BEECK, ALEXANDER;NAGLER, CHRISTOPH;RICHTER, MARK;REEL/FRAME:012630/0577 Effective date: 20020227 |
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Owner name: ALSTOM TECHNOLOGY LTD, SWITZERLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ALSTOM (SWITZERLAND) LTD;REEL/FRAME:014770/0783 Effective date: 20031101 |
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STCH | Information on status: patent discontinuation |
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